Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide-completion/src/completions/flyimport.rs')
-rw-r--r--crates/ide-completion/src/completions/flyimport.rs268
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diff --git a/crates/ide-completion/src/completions/flyimport.rs b/crates/ide-completion/src/completions/flyimport.rs
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+++ b/crates/ide-completion/src/completions/flyimport.rs
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+//! See [`import_on_the_fly`].
+use hir::{ItemInNs, ModuleDef};
+use ide_db::imports::{
+ import_assets::{ImportAssets, ImportCandidate, LocatedImport},
+ insert_use::ImportScope,
+};
+use itertools::Itertools;
+use syntax::{AstNode, SyntaxNode, T};
+
+use crate::{
+ context::{CompletionContext, PathKind},
+ patterns::ImmediateLocation,
+ render::{render_resolution_with_import, RenderContext},
+};
+
+use super::Completions;
+
+// Feature: Completion With Autoimport
+//
+// When completing names in the current scope, proposes additional imports from other modules or crates,
+// if they can be qualified in the scope, and their name contains all symbols from the completion input.
+//
+// To be considered applicable, the name must contain all input symbols in the given order, not necessarily adjacent.
+// If any input symbol is not lowercased, the name must contain all symbols in exact case; otherwise the containing is checked case-insensitively.
+//
+// ```
+// fn main() {
+// pda$0
+// }
+// # pub mod std { pub mod marker { pub struct PhantomData { } } }
+// ```
+// ->
+// ```
+// use std::marker::PhantomData;
+//
+// fn main() {
+// PhantomData
+// }
+// # pub mod std { pub mod marker { pub struct PhantomData { } } }
+// ```
+//
+// Also completes associated items, that require trait imports.
+// If any unresolved and/or partially-qualified path precedes the input, it will be taken into account.
+// Currently, only the imports with their import path ending with the whole qualifier will be proposed
+// (no fuzzy matching for qualifier).
+//
+// ```
+// mod foo {
+// pub mod bar {
+// pub struct Item;
+//
+// impl Item {
+// pub const TEST_ASSOC: usize = 3;
+// }
+// }
+// }
+//
+// fn main() {
+// bar::Item::TEST_A$0
+// }
+// ```
+// ->
+// ```
+// use foo::bar;
+//
+// mod foo {
+// pub mod bar {
+// pub struct Item;
+//
+// impl Item {
+// pub const TEST_ASSOC: usize = 3;
+// }
+// }
+// }
+//
+// fn main() {
+// bar::Item::TEST_ASSOC
+// }
+// ```
+//
+// NOTE: currently, if an assoc item comes from a trait that's not currently imported, and it also has an unresolved and/or partially-qualified path,
+// no imports will be proposed.
+//
+// .Fuzzy search details
+//
+// To avoid an excessive amount of the results returned, completion input is checked for inclusion in the names only
+// (i.e. in `HashMap` in the `std::collections::HashMap` path).
+// For the same reasons, avoids searching for any path imports for inputs with their length less than 2 symbols
+// (but shows all associated items for any input length).
+//
+// .Import configuration
+//
+// It is possible to configure how use-trees are merged with the `importMergeBehavior` setting.
+// Mimics the corresponding behavior of the `Auto Import` feature.
+//
+// .LSP and performance implications
+//
+// The feature is enabled only if the LSP client supports LSP protocol version 3.16+ and reports the `additionalTextEdits`
+// (case-sensitive) resolve client capability in its client capabilities.
+// This way the server is able to defer the costly computations, doing them for a selected completion item only.
+// For clients with no such support, all edits have to be calculated on the completion request, including the fuzzy search completion ones,
+// which might be slow ergo the feature is automatically disabled.
+//
+// .Feature toggle
+//
+// The feature can be forcefully turned off in the settings with the `rust-analyzer.completion.autoimport.enable` flag.
+// Note that having this flag set to `true` does not guarantee that the feature is enabled: your client needs to have the corresponding
+// capability enabled.
+pub(crate) fn import_on_the_fly(acc: &mut Completions, ctx: &CompletionContext) -> Option<()> {
+ if !ctx.config.enable_imports_on_the_fly {
+ return None;
+ }
+ if matches!(ctx.path_kind(), Some(PathKind::Vis { .. } | PathKind::Use))
+ || ctx.is_path_disallowed()
+ || ctx.expects_item()
+ || ctx.expects_assoc_item()
+ || ctx.expects_variant()
+ {
+ return None;
+ }
+ // FIXME: This should be encoded in a different way
+ if ctx.pattern_ctx.is_none() && ctx.path_context.is_none() && !ctx.has_dot_receiver() {
+ // completion inside `ast::Name` of a item declaration
+ return None;
+ }
+ let potential_import_name = {
+ let token_kind = ctx.token.kind();
+ if matches!(token_kind, T![.] | T![::]) {
+ String::new()
+ } else {
+ ctx.token.to_string()
+ }
+ };
+
+ let _p = profile::span("import_on_the_fly").detail(|| potential_import_name.clone());
+
+ let user_input_lowercased = potential_import_name.to_lowercase();
+ let import_assets = import_assets(ctx, potential_import_name)?;
+ let position = position_for_import(ctx, Some(import_assets.import_candidate()))?;
+ if ImportScope::find_insert_use_container(&position, &ctx.sema).is_none() {
+ return None;
+ }
+
+ let path_kind = match ctx.path_kind() {
+ Some(kind) => Some(kind),
+ None if ctx.pattern_ctx.is_some() => Some(PathKind::Pat),
+ None => None,
+ };
+ let ns_filter = |import: &LocatedImport| {
+ let path_kind = match path_kind {
+ Some(path_kind) => path_kind,
+ None => match import.original_item {
+ ItemInNs::Macros(mac) => return mac.is_fn_like(ctx.db),
+ _ => return true,
+ },
+ };
+ match (path_kind, import.original_item) {
+ // Aren't handled in flyimport
+ (PathKind::Vis { .. } | PathKind::Use, _) => false,
+ // modules are always fair game
+ (_, ItemInNs::Types(hir::ModuleDef::Module(_))) => true,
+ // and so are macros(except for attributes)
+ (
+ PathKind::Expr | PathKind::Type | PathKind::Mac | PathKind::Pat,
+ ItemInNs::Macros(mac),
+ ) => mac.is_fn_like(ctx.db),
+ (PathKind::Mac, _) => true,
+
+ (PathKind::Expr, ItemInNs::Types(_) | ItemInNs::Values(_)) => true,
+
+ (PathKind::Pat, ItemInNs::Types(_)) => true,
+ (PathKind::Pat, ItemInNs::Values(def)) => matches!(def, hir::ModuleDef::Const(_)),
+
+ (PathKind::Type, ItemInNs::Types(ty)) => {
+ if matches!(ctx.completion_location, Some(ImmediateLocation::TypeBound)) {
+ matches!(ty, ModuleDef::Trait(_))
+ } else {
+ true
+ }
+ }
+ (PathKind::Type, ItemInNs::Values(_)) => false,
+
+ (PathKind::Attr { .. }, ItemInNs::Macros(mac)) => mac.is_attr(ctx.db),
+ (PathKind::Attr { .. }, _) => false,
+
+ (PathKind::Derive, ItemInNs::Macros(mac)) => {
+ mac.is_derive(ctx.db) && !ctx.existing_derives.contains(&mac)
+ }
+ (PathKind::Derive, _) => false,
+ }
+ };
+
+ acc.add_all(
+ import_assets
+ .search_for_imports(&ctx.sema, ctx.config.insert_use.prefix_kind)
+ .into_iter()
+ .filter(ns_filter)
+ .filter(|import| {
+ !ctx.is_item_hidden(&import.item_to_import)
+ && !ctx.is_item_hidden(&import.original_item)
+ })
+ .sorted_by_key(|located_import| {
+ compute_fuzzy_completion_order_key(
+ &located_import.import_path,
+ &user_input_lowercased,
+ )
+ })
+ .filter_map(|import| render_resolution_with_import(RenderContext::new(ctx), import))
+ .map(|builder| builder.build()),
+ );
+ Some(())
+}
+
+pub(crate) fn position_for_import(
+ ctx: &CompletionContext,
+ import_candidate: Option<&ImportCandidate>,
+) -> Option<SyntaxNode> {
+ Some(
+ match import_candidate {
+ Some(ImportCandidate::Path(_)) => ctx.name_syntax.as_ref()?.syntax(),
+ Some(ImportCandidate::TraitAssocItem(_)) => ctx.path_qual()?.syntax(),
+ Some(ImportCandidate::TraitMethod(_)) => ctx.dot_receiver()?.syntax(),
+ None => return ctx.original_token.parent(),
+ }
+ .clone(),
+ )
+}
+
+fn import_assets(ctx: &CompletionContext, fuzzy_name: String) -> Option<ImportAssets> {
+ let current_module = ctx.module;
+ if let Some(dot_receiver) = ctx.dot_receiver() {
+ ImportAssets::for_fuzzy_method_call(
+ current_module,
+ ctx.sema.type_of_expr(dot_receiver)?.original,
+ fuzzy_name,
+ dot_receiver.syntax().clone(),
+ )
+ } else {
+ let fuzzy_name_length = fuzzy_name.len();
+ let mut assets_for_path = ImportAssets::for_fuzzy_path(
+ current_module,
+ ctx.path_qual().cloned(),
+ fuzzy_name,
+ &ctx.sema,
+ ctx.token.parent()?,
+ )?;
+ if fuzzy_name_length < 3 {
+ cov_mark::hit!(flyimport_exact_on_short_path);
+ assets_for_path.path_fuzzy_name_to_exact(false);
+ }
+ Some(assets_for_path)
+ }
+}
+
+pub(crate) fn compute_fuzzy_completion_order_key(
+ proposed_mod_path: &hir::ModPath,
+ user_input_lowercased: &str,
+) -> usize {
+ cov_mark::hit!(certain_fuzzy_order_test);
+ let import_name = match proposed_mod_path.segments().last() {
+ Some(name) => name.to_smol_str().to_lowercase(),
+ None => return usize::MAX,
+ };
+ match import_name.match_indices(user_input_lowercased).next() {
+ Some((first_matching_index, _)) => first_matching_index,
+ None => usize::MAX,
+ }
+}